Siman 482
Presented here for study, not as a practical ruling. The Shulchan Aruch rules by Sephardi custom, the Rema's glosses by Ashkenazi custom, and the Kitzur follows Ashkenazi custom. For a practical question, ask your rabbi.
א מִי שֶׁאֵין לוֹ מַצָּה מְשֻׁמֶּרֶת אֶלָּא כַּזַּיִת, מְבָרֵךְ עַל אֲכִילַת מָרוֹר וְאוֹכֵל, וּכְשֶׁגּוֹמֵר סְעוּדָתוֹ מִמַּצָּה שֶׁאֵינָהּ מְשֻׁמֶּרֶת, מְבָרֵךְ עַל אֲכִילַת מַצָּה וְאוֹכֵל אוֹתוֹ כַּזַּיִת, וְאֵינוֹ טוֹעֵם אַחֲרָיו כְּלוּם. הַגָּה: וּמִי שֶׁאֵין לוֹ ב' הַלֵּילוֹת רַק ג' מַצּוֹת, יְבָרֵךְ לַיִל רִאשׁוֹן הַמּוֹצִיא וְעַל אֲכִילַת מַצָּה וְכֵן הַכְּרִיכָה הַכֹּל מִן הַפְּרוּסָה, וּשְׁתֵּי הַשְּׁלֵמוֹת לְלֵיל ב'. (אַבּוּדַרְהַם בְּשֵׁם אִבְּן יַרְחִי).
1 The law of one who does not have protected matzah. Containing 1 paragraph: One who only has a olive-size portion of matza recites the blessing of, "about eating bitter herbs," and eats [them]. And when he finishes his meal with matza that was not protected, he recites the blessing, "about eating matza," eats that kazayit and does not eat anything after it. Rema: And one who only has three matzot for the [first] two nights should recite on the first night, "about eating matza" and "who brings forth (ha-motzi) - and likewise with the sandwich (of matza and bitter herbs) - all upon the [first] piece; and the two matzot are [held] for the second night. (Abudarham in the name of Ibn Yarchi)